One of the great things about this list is the opportunity it affords to admit when you (me) are mistaken. I have played around with a shadow sharpener, and can now see that it really does project a small, fairly sharp, central shadow narrower than the 2 minute width of the solar disk. I think it would make an ideal device for use with an annalematic noon mark. I have attached a .gif of how I think the sharpener works, if anyone is interested.
Bill Gottesman Burlington, VT 44.4674 N 73.2027 W Attachment converted: Macintosh HD:SHADOW SHARPENER.gif (GIFf/JVWR) (000125EF)
